AU2018249158B2 - Hardener for two-pack type adhesive, two-pack type adhesive, laminated film, and package - Google Patents

Abstract

A hardener for two-pack type adhesives which comprises a reaction product (B-1) obtained by reacting a polyol with one or more isocyanate compounds comprising 4,4'-diphenylmethane diisocyanate and at least one isocyanate compound (B-2) selected from the group consisting of isocyanates each in the forms of isocyanurate, biuret, allophanate, and adduct; a two-pack type adhesive which comprises a polyol component A comprising a polyol compound and an isocyanate component B comprising one or more isocyanate compounds, wherein the isocyanate component B includes the isocyanate compound (B-2); and a laminated film and a package each obtained using the two-pack type adhesive.

Description

DESCRIPTION

Title of Invention: HARDENER FOR TWO-PACK TYPE ADHESIVE,

TWO-PACK TYPE ADHESIVE, LAMINATED FILM, AND PACKAGE

Technical Field

[0001]

The present invention relates to a hardener for a

two-component adhesive, a two-component adhesive, and a

laminated film, and a package formed using the same.

Background Art

[0002]

Laminated films (also referred to as laminate films in

some cases) used for various packaging materials, labels, and

the like are laminated with various kinds of plastic films,

metal foils, paper, and the like to impart designs,

functionality, preservation, convenience, and

transportability thereto, and, in particular, packages formed

by forming the laminated film into a bag shape are used as

packages for food, medicine, detergents, and the like.

[0003]

In the related art, laminated films are mainly obtained

using a dry lamination method in which an adhesive (may be

referred to as a solvent type lamination adhesive) dissolved

in a volatile organic solvent is applied to the film, the organic solvent is volatilized while passing through an oven, and another film is adhered thereto; however, in recent years, from the viewpoint of reducing the environmental burden and improving the working environment, there has been an increasing demand for a reactive two-component lamination adhesive which does not contain volatile organic solvents (may be referred to as a two-component adhesive or a solvent-free lamination adhesive). (For example, refer to PTL 1)

[0004]

Although the two-component adhesive described in PTL 1

is effective for the adhesive strength and for shortening the

aging time in a solvent-free adhesive, since the two-component

adhesive combines an aromatic isocyanate as a hardener and a

polyester diol as a main agent, the resin for the solvent-free

adhesive had a short relative pot life. In a case where the

pot life is short, there is a concern that variations in the

coating amount will easily occur and that the appearance of

the laminate will be significantly impaired as a result, and

there is also a concern that there will be a need for operations

such as replacement of the adhesive or cleaning of the roll

in a case where the laminating apparatus is temporarily stopped,

such as at the time of raw material replacement, and the

workability may be significantly impaired. In particular, in

a case where 4,4'-diphenylmethane diisocyanate (MDI), which

is an aromatic isocyanate, is used as a hardener, since the compound has high crystallinity, there is a concern that the hardener itself may be crystallized or precipitated.

[00051

Furthermore, since a two-component adhesive uses a

reactive monomer having amolecular weight slightly lower than

that of a solvent-type lamination adhesive as a raw material,

there is a possibility of elution into the contents through

the film after lamination. In particular, in recent years,

starting in Europe, regulations for components which elute

(transfer) chemical substances from plastic containers have

come to be more strictly defined and there is a demand for

products which contain fewer components which elute chemical

substances from the container. Regarding the elution of

chemical substances generally used in adhesives, the Specific

Migration Limit (SML) is defined, and it is possible to easily

control the eluates, but there is a problem in that it is not

possible to easily eliminate the elution of non-intentionally

added substances (NIAS) generated by synthesis or the like.

[00061

On the other hand, it is known that adhesives which

include an isocyanate terminal polyurethane prepolymer, which

is a reaction product of a modified diphenylmethane

diisocyanate (MDI), which is selected from the group

consisting of carbodiimide modified diphenylmethane

diisocyanate, allophanate modified diphenylmethane diisocyanate, biuret modified diphenylmethane diisocyanate, polymeric diphenylmethane diisocyanate, and combinations thereof, and a polyol, are adhesives which generate low concentrations of extractable primary aromatic amines (PAA)

(refer to, for example, PTL2). However, since these adhesives

are used by reacting the modified diphenylmethane diisocyanate

with a polyol, the viscosity is easily increased and there is

still a tendency for the pot life to be short.

Accordingly, a two-component adhesive with little

non-intentional substance elution and a long pot life which

is satisfactory in practice has not yet been obtained.

Citation List

Patent Literature

[0007]

PTL 1: JP-A-2014-159548

PTL 2: JP-T-2014-516321

[0007A]

Any discussion of documents, acts, materials, devices,

articles or the like which has been included in the present

specification is not to be taken as an admission that any or

all of these matters form part of the prior art base or were

common general knowledge in the field relevant to the present

disclosure as it existed before the priority date of each of

the appended claims.

Summary of Invention

[0007B]

Throughout this specification the word "comprise", or

variations such as "comprises" or "comprising", will be

understood to imply the inclusion of a stated element, integer

or step, or group of elements, integers or steps, but not the

exclusion of any other element, integer or step, or group of

elements, integers or steps.

Technical Problem

[00081

The problem to be solved by the present invention is to

provide a two-component adhesive for which a hardener itself

has excellent long-term storability and which, when used as

a two-component adhesive, has extremely few non-intentional

substances which elute into the contents through the film after

lamination and a long pot life.

4A

Solution to Problem

[00091

The presentinventors found thatit was possible to solve

the problem described above with a hardener for a two-component

adhesive which contains a reaction product (B-1) of a polyol

and an isocyanate compound including at least

4,4'-diphenylmethane diisocyanate and the isocyanate compound

(B-2), and a two-component adhesive using this hardener.

[0010]

That is, the present invention provides a hardener for

a two-component adhesive, including the reactionproduct (B-1)

of a polyol and an isocyanate compound including at least

4,4'-diphenylmethane diisocyanate, and at least one

isocyanate compound (B-2) selected from the group consisting

of a diisocyanate isocyanurate, a diisocyanate biuret, a

diisocyanate allophanate, and a diisocyanate adduct.

[0011]

In addition, the present invention provides a

two-component adhesive including: a polyol component A

including a polyol compound; and an isocyanate component B

including an isocyanate compound, in which the isocyanate

component B includes the reaction product (B-1) of a polyol

and an isocyanate compound including at least

4,4'-diphenylmethane diisocyanate, and at least one

isocyanate compound (B-2) selected from the group consisting of a diisocyanate isocyanurate, a diisocyanate biuret, a diisocyanate allophanate, and a diisocyanate adduct.

[0012]

In addition, the present invention provides a laminated

film including a laminate of a first plastic film, a second

plasticfilm, andan adhesive layerbetween the first andsecond

plastic films, in which the adhesive layer is a layer of the

two-component adhesive described above.

[0013]

In addition, the present invention provides a package

including a bag-shaped laminated film including a laminate of

a first plastic film, a second plastic film, and an adhesive

layer between the first and second plastic films, in which the

adhesive layer is a layer of the two-component adhesive

described above.

Advantageous Effects of Invention

[0014]

According to the present invention, the hardener itself

has excellent long-term storability and, when used as a

two-component adhesive, has extremely few non-intentional

substances whichelute into the contents through the filmafter

lamination, thus, peeling of the laminate structure, such as

delamination, does not occur at the time of filling contents

such as detergents and drugs therein or after time passes from

the filling and the adhesion and resistance to the contents are excellent. In addition, since the viscosity is low and the pot life is long, the workability after blending the adhesive is excellent.

Description of Embodiments

[0015]

(Definition: Solvent)

The two-component adhesive of the present invention is

a reactive two-component lamination adhesive as described

above, and is also referred to as a solvent-free lamination

adhesive since the volatile organic solvents of the related

art are not used.

In the present invention, an adhesive which is cured

through a chemical reaction between an isocyanate group and

a hydroxyl group is used. Here, the "solvent" of the

non-solvent type adhesive referred to in the present invention

indicates a highly soluble and volatile organic solvent which

is capable of dissolving the polyisocyanate or polyol used in

the present invention, while "solvent-free" indicates that

these highly soluble organic solvents are not included.

Specifically, examples of organic solvents having high

solubility include toluene, xylene, methylene chloride,

tetrahydrofuran, methyl acetate, ethyl acetate, n-propyl

acetate, n-butyl acetate, acetone, methyl ethyl ketone (MEK),

cyclohexanone, toluol, xylol, n-hexane, cyclohexane, and the

like. Among the above, toluene, xylene, methylene chloride, tetrahydrofuran, methyl acetate, and ethyl acetate are known as organic solvents which are particularly highly soluble.

[00161

On the other hand, in a case where there is a demand for

the adhesive of the present invention to have a low viscosity

or the like, the adhesive may be used after being appropriately

diluted with the highly soluble organic solvent according to

the desired viscosity. In such a case, either one of the polyol

component A or the isocyanate component B may be diluted or

both may be diluted. Examples of the organic solvents used

in such a case include methyl acetate, ethyl acetate, n-propyl

acetate, n-butyl acetate, acetone, methyl ethyl ketone (MEK),

cyclohexanone, toluol, xylol, n-hexane, cyclohexane, and the

like. Among the above, in terms of solubility, ethyl acetate

and methyl ethyl ketone (MEK) are preferable and ethyl acetate

is particularly preferable. The usage amount of the organic

solvent depends on the required viscosity, but is often in the

range of approximately 0.1 to 10% by mass.

In addition, in order to achieve a reduction in the

viscosity of the adhesive of the present invention, a solvent

with a boiling point 200°C or more which has a carbonyl group

and which does not have a hydroxyl group, such as triacetin

or propylene carbonate, may be used. The usage amount of the

high boiling point organic solvent depends on the required

viscosity and the coated film properties, but is often in the range of approximately 0.1 to 10% by mass.

[0017]

(Definition: Main Agent, Hardener)

In general, in two-component adhesives, there are

various expressions for expressing the "two-packs", but, in

the present invention, the isocyanate component B containing

an isocyanate compound is referred to as a "hardener" and the

polyol component A containing a polyol compound is referred

to as a "main agent".

[0018]

(Main Agent: Polyol Component A Containing Polyol

Compound)

It is possible to use a well-known polyol for the polyol

compoundcontaining the polyolcomponent Awhichis amain agent

in the present invention, without being particularly limited.

Examples thereof include polymer polyols selected from

polyester polyols, polyether polyols, polyurethane polyols,

polyether ester polyols, polyester (polyurethane) polyols,

polyether (polyurethane) polyols, polyesteramide polyols,

acrylicpolyols, polycarbonate polyols, polyhydroxyl alkanes,

castor oil, or mixtures thereof.

[0019]

Specific examples thereof include glycols such as

ethylene glycol, propylene glycol, 1,3-propanediol,

1,4-butanediol, 1,5-pentanediol, 3-methyl-1,5-pentanediol,

1,6-hexanediol, neopentyl glycol, methylpentanediol,

dimethylbutanediol, butylethylpropanediol, diethylene glycol,

triethylene glycol, tetraethylene glycol, dipropylene glycol,

tripropylene glycol, bishydroxyethoxybenzene,

1,4-cyclohexanediol, 1,4-cyclohexanedimethanol, and

triethylene glycol; trifunctional or tetrafunctional fatty

alcohols such as glycerin, trimethylolpropane,

pentaerythritol, and triol of polypropylene glycol;

bisphenols such as bisphenol A, bisphenol F, hydrogenated

bisphenol A, and hydrogenated bisphenol F; dimer diols;

[0020]

Polyether polyols obtained by addition polymerization

of alkylene oxides such as ethylene oxide, propylene oxide,

butylene oxide, styrene oxide, epichlorohydrin,

tetrahydrofuran, and cyclohexylene in the presence of a

polymerization initiator such as glycols or trifunctional or

tetrafunctional aliphatic alcohols; polyether urethane

polyols obtained by further polymerizing the polyether polyol

with an aromatic or aliphatic polyisocyanate;

[0021]

Polyester polyol (1), which is a reaction product of a

polyester obtained by a ring-opening polymerization reaction

ofcyclicester compounds such as propiolactone, butyrolactone,

e-caprolactone, G-valerolactone, and

$-methyl-a-valerolactone and a polyhydric alcohol such as glycol, glycerin, trimethylolpropane, and pentaerythritol; polyester polyol (2) obtained by reacting the glycol, dimer diols, or the bifunctional polyol such as bisphenol with a polyvalent carboxylic acid; polyester polyol (3) obtained by reacting the trifunctional or tetrafunctional aliphatic alcohol with a polyvalent carboxylic acid; polyester polyol (4) obtained by reacting the glycol, dimer diols, or the bifunctional polyol such as bisphenol, the trifunctional or tetrafunctional aliphatic alcohol, and polyvalent carboxylic acid; polyester polyol (5) which is a polymer of hydroxyl acid such as dimethylol propionic acid or castor oil fatty acid; polyester polyether polyols obtainedby reacting the polyester polyols (1) to (5), the polyether polyols, and aromatic or aliphatic polyisocyanates; polyester polyurethane polyols obtained by polymerizing the polyester polyols (1) to (5) with aromatic or aliphatic polyisocyanate; mixtures of polyester polyols (1) to (5) with polyether polyols; castor oil, dehydrated castor oil, hardened castor oil which is a hydrogenated product of castor oil, castor oil-based polyols such as 5 to 50 mole adducts of alkylene oxide of castor oil, and copolymers of these castor oil-based polyols and the glycol, dimer diols, or the bifunctional polyol such as bisphenol.

[0022]

Here, examples of polyvalent carboxylic acids include

aliphatic dicarboxylic acids such as succinic acid, adipic

acid, azelaic acid, sebacic acid, dodecanedicarboxylic acid,

maleic anhydride, fumaric acid, 1,3-cyclopentanedicarboxylic

acid, and 1,4-cyclohexanedicarboxylic acid; aromatic

dicarboxylicacids such as terephthalicacid, isophthalicacid,

1,4-naphthalenedicarboxylic acid,

2,5-naphthalenedicarboxylic acid,

2,6-naphthalenedicarboxylic acid, naphthalic acid,

biphenyldicarboxylic acid, and 1,2-bis (phenoxy)

ethane-p,p'-dicarboxylic acid; anhydrides or ester-forming

derivatives of these aliphatic or dicarboxylic acids;

polybasic acids such as p-hydroxybenzoic acid,

p-(2-hydroxyethoxy) benzoic acid, and ester-forming

derivatives of these dihydroxycarboxylic acids, and dimer

acids.

[0023]

The polyurethane polyol is a reaction product of a

polyether polyol having a number average molecular weight of

200 to 20,000 and an organic polyisocyanate, and NCO/OH is

preferably less than 1, and more preferably 0.9 or less.

[0024]

Polyether (polyurethane) polyol and polyester

(polyurethane) polyol are reaction products of polyester

polyol, polyether ester polyol, and the like and an organic

polyisocyanate, and NCO/OH is preferably less than 1, and more

preferably 0.9 or less.

[0025]

It is possible to obtain the polyesteramide polyol, for

example, by combining and esterifying an aliphatic diamine

having an amino group such as ethylenediamine,

propylenediamine, or hexamethylenediamine as a raw material.

Examples of acrylic polyols may be obtained by

copolymerizing hydroxyethyl acrylate, hydroxypropyl acrylate,

hydroxybutyl acrylate or the like including one or more

hydroxyl groups in one molecule, or methacrylic acid

derivatives corresponding thereto, and the like, and, for

example, acrylic acid, methacrylic acid, or esters thereof.

[0026]

The polycarbonate polyols may be obtained by reacting

one type or two or more types of glycols selected from among

ethylene glycol, propylene glycol, 1,4-butanediol,

1,5-pentanediol, 1,6-hexanediol, 3-methyl-1,5-pentanediol,

1,9-nonanediol, 1,8-nonanediol, neopentyl glycol, diethylene

glycol, dipropylene glycol, 1,4-cyclohexanediol,

1,4-cyclohexanedimethanol, bisphenol A, and hydrogenated

bisphenol A with dimethyl carbonate, diphenyl carbonate, ethylene carbonate, phosgene, and the like.

[0027]

Examples of polyhydroxyalkanes include butadiene, and

liquid rubbers obtained by copolymerizing butadiene with

acrylamide or the like.

Among these, polyether (polyurethane) polyols are

particularly preferable.

[0028]

In addition, as a polyol compound used in the present

invention, it is also possible to preferably use a compound

which is a reaction product of polyisocyanate and bis

(hydroxyalkyl) amine and which has a urea bonding group at the

terminal.

[0029]

In the present invention, among the above, a polyester

polyol (4) obtained by reacting a bifunctional polyol, the

trifunctional or tetrafunctional aliphatic alcohol, and a

polyvalent carboxylic acid, or a copolymer of a castor

oil-based polyol and the glycol, dimer diols, or the

bifunctional polyol such as bisphenol is preferable. As the

trifunctional or tetrafunctional aliphatic alcohol, a triol

of glycerin or polypropylene glycol is preferable.

[0030]

The number average molecular weight of the polyol

component A is not particularly limited, but is usually often adjusted in the range of 500 to 3000 from the viewpoint of appropriate resin viscosity at the time of coating.

[0031]

In the present invention, the number average molecular

weight (Mn) is a value measured by gel permeation

chromatography (GPC) under the following conditions.

[0032]

Measuring device: HLC-8220 GPC manufactured by Tosoh

Corporation

Column: TSK-GUARDCOLUMN SuperHZ-L manufactured by Tosoh

Corporation

+ TSK-GEL SuperHZM-M x 4 manufactured by Tosoh Corporation

Detector: Refractive Index Detector (RI)

Data processing: Multistation GPC-8020 model III manufactured

by Tosoh Corporation

Measurement conditions: column temperature 40°C

Solvent Tetrahydrofuran

Flow rate 0.35 ml/min

Standard; Monodisperse polystyrene

Sample: A 0.2% by mass tetrahydrofuran solution in terms of

resin solid content filtered with a microfilter (100 pl)

[0033]

(Hardener: Isocyanate component B including an isocyanate

compound)

The isocyanate component B which is a hardener in the present invention includes the reaction product (B-1) of a polyol and an isocyanate compound including at least

4,4'-diphenylmethane diisocyanate, and at least one

isocyanate compound (B-2) selected from the group consisting

of a diisocyanate isocyanurate, a diisocyanate biuret, a

diisocyanate allophanate, and a diisocyanate adduct.

[0034]

(Reaction product (B-1) of polyol and isocyanate compound

including at least 4,4'-diphenylmethane diisocyanate)

As a reaction rawmaterialof the reactionproduct (B-1),

4,4'-diphenylmethane diisocyanate is essential.

Examples of other isocyanate compounds which may be

included as reaction raw materials include aromatic

diisocyanates other than 4,4'-diphenylmethane diisocyanate,

araliphatic diisocyanates, aliphatic diisocyanates,

alicyclic diisocyanates; biurets, nurates, adducts, and

allophanates of diisocyanate; carbodiimide modified

isocyanate, urethane prepolymers obtained by reacting an

isocyanate and a polyol, and the like, and it is possible to

use these alone or in combination.

[0035]

Examples of aromatic diisocyanates include

2,2'-diphenylmethane diisocyanate, 2,4'-diphenylmethane

diisocyanate, 1,3-phenylene diisocyanate, 4,4'-diphenyl

diisocyanate, 1,4-phenylene diisocyanate, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 4,4'-toluidine diisocyanate, 2,4,6-triisocyanate toluene,

1,3,5-triisocyanate benzene, dianisidine diisocyanate,

4,4'-diphenyl ether diisocyanate, 4,4',4' '-triphenylmethane

triisocyanate, and the like, without being limited thereto.

[00361

For example, an aromatic aliphatic diisocyanate

indicates an aliphatic isocyanate having one or more aromatic

rings in the molecule, and examples thereof include m- or

p-xylylene diisocyanate (also known as XDI),

ax,,a','-tetramethyl xylylene diisocyanate (also known as

TMXDI), and the like, without being limited thereto.

[0037]

Examples of aliphatic diisocyanates include

trimethylene diisocyanate, tetramethylene diisocyanate,

hexamethylene diisocyanate (also known as HDI),

pentamethylene diisocyanate, 1,2-propylene diisocyanate,

2,3-butylene diisocyanate, 1,3-butylene diisocyanate

dodecamethylene diisocyanate, 2,4,4-trimethylhexamethylene

diisocyanate, and the like, without being limited thereto.

[00381

Examples of alicyclic diisocyanates include

3-isocyanatomethyl-3,5,5-trimethylcyclohexyl isocyanate,

isophorone diisocyanate (also known as IPDI),

1,3-cyclopentadiisocyanate, 1,3-cyclohexane diisocyanate,

1,4-cyclohexanediisocyanate,

methyl-2,4-cyclohexanediisocyanate,

methyl-2,6-cyclohexanediisocyanate, 4,4'-methylenebis

(cyclohexylisocyanate), 1,4-bis (isocyanatomethyl)

cyclohexane and the like, without being limited thereto.

[00391

In the present invention, 4,4'-diphenylmethane

diisocyanate, which is a raw material of the reaction product

(B-1), is preferably used in a range of 50 to 99% by weight

based on the total weight of all isocyanate compounds of the

reaction product (B-1), and more preferably used in a range

of 90 to 99% by weight.

[0040]

Examples of polyol which is a raw material of the reaction

product (B-1) include alkylene glycols such as ethylene glycol,

propylene glycol, 1,3-propanediol, 1,4-butanediol,

1,5-pentanediol, 3-methyl-1,5-pentanediol, 1,6-hexanediol,

neopentyl glycol, methylpentanediol, dimethylbutanediol,

butylethylpropanediol, 1,4-cyclohexanediol, and

1,4-cyclohexanedimethanol; bisphenols such as bisphenol A,

bisphenol F, hydrogenated bisphenol A, and hydrogenated

bisphenol F; dimer diols; bishydroxy ethoxy benzene;

polyalkylene glycols such as diethylene glycol, triethylene

glycol, other polyethylene glycols, polypropylene glycol, and

polybutylene glycol; urethane bond-containing polyether polyols obtained by further increasing the molecular weight of the polyalkylene glycol with the aromatic or aliphatic polyisocyanate; andpolyester polyols obtainedby reacting the alkylene glycol or polyalkylene glycol with an aliphatic dicarboxylic acid having 2 to 13 carbon atoms such as oxalic acid, malonicacid, succinicacid, glutaricacid, adipicacid, fumaricacid, maleicacid, suberic acid, azelaicacid, sebacic acid, undecanedioic acid, dodecanedioic acid, and tridecanedioic acid; polyester polyols which are a reaction product of a polyester obtained by a ring-opening polymerization reaction of a cyclic ester compound such as propiolactone, butyrolactone, e-caprolactone,

G-valerolactone, and $-methyl-a-valerolactone and a

polyhydric alcohol such as the glycol, glycerine,

trimethylolpropane, and pentaerythritol.

[0041]

In terms of increasing the adhesive strength while

lowering the viscosity of the adhesive itself, the polyol is

preferably polyalkylene glycol or polyester polyol, among the

above, and the polyalkylene glycol preferably has a number

average molecular weight (Mn) in a range of 200 to 6,000. On

the other hand, the polyester polyol is preferably obtained

by reacting an alkylene glycol or polyalkylene glycol having

a molecular weight of 300 or less with an aliphatic polyvalent

carboxylic acid having 2 to 30 carbon atoms. The latter polyester polyolmay also be obtained using, as a raw material, a tri- or more-functional alcohol such as glycerin, trimethylolpropane, or pentaerythritol at a concentration of

10% by mass of less based on the mass of the polyol components.

[0042]

Among the above reaction products (B-1), a

polyisocyanate obtained by reacting 4,4'-diphenylmethane

diisocyanate with polyalkylene glycol having a number average

molecular weight in a range of200 to 6,000 and apolyisocyanate

obtained by reacting 4,4'-diphenylmethane diisocyanate with

a polyester polyol having a number average molecular weight

in the range of 200 to 3,000 are preferable as a soft packaging

base material in terms of imparting appropriate flexibility

to a cured product, specifically, a polyisocyanate with an

isocyanate content ratio of 5 to 20% by mass according to a

titration method (using di-n-butylamine) is preferable in

terms of obtaining an appropriate resin viscosity and

excellent coatability.

[0043]

On the other hand, a polyisocyanate obtained by reacting

4,4'-diphenylmethane diisocyanate with a polyester polyol

having a number average molecular weight of 200 to 3,000 and

a polyisocyanate obtained by reacting 4,4'-diphenylmethane

diisocyanate with a mixture of a polyester polyol having a

number average molecular weight of 200 to 3,000 and a polyalkylene glycol having a number average molecular weight of 200 to 6,000 are preferable as a hard base material of a two-component adhesive in terms ofexcellent adhesion strength, specifically, a polyisocyanate having an isocyanate content ratio of 5 to 20% by mass according to a titration method (using di-n-butylamine) is preferable in terms of obtaining an appropriate resin viscosity and excellent coatability.

[0044]

Here, the reaction ratio between 4,4'-diphenylmethane

diisocyanate and the mixture of the polyalkylene glycol or the

polyester polyol is such that the equivalent ratio

[isocyanate/hydroxyl group] of the isocyanate in the

4,4'-diphenylmethane diisocyanate to the hydroxylgroup in the

polyolis in a range of 1.5 to 5.0, which is preferable in terms

of the viscosity of the adhesive being in an appropriate range

and the coatability being favorable.

[0045]

The number average molecular weight of the reaction

product (B-1) is preferably in the range of 500 to 3,000, and

more preferably 500 to 1,500 from the viewpoint of an

appropriate resin viscosity at the time of coating.

[0046]

(Isocyanate compound (B-2))

The isocyanate component B which is a hardener in the

present invention includes at least one isocyanate compound

(B-2) selected from the group consisting of a diisocyanate

isocyanurate, a diisocyanate biuret, a diisocyanate

allophanate, and a diisocyanate adduct in addition to the

reaction product (B-1). These isocyanate compounds (B-2) may

be used alone or in a combination of two or more types.

[0047]

The isocyanurate, biuret, and allophanate are dimers or

trimers of a diisocyanate compound, and these diisocyanate

compounds are aliphatic diisocyanate compounds such as butane

diisocyanate, hexamethylene diisocyanate,

2,2,4-trimethylhexamethylene diisocyanate,

2,4,4-trimethylhexamethylene diisocyanate, xylylene

diisocyanate, and m-tetramethyl xylylene diisocyanate;

[0048]

Alicyclic diisocyanate compounds such as cyclohexane

diisocyanate, isophorone diisocyanate, lysine diisocyanate,

dicyclohexylmethane-4,4'-diisocyanate, bis (isocyanate

methyl) cyclohexane, and methylcyclohexane diisocyanate; and

[0049]

aromaticdiisocyanate compounds such as 1,5-naphthylene

diisocyanate, 4,4'-diphenylmethane diisocyanate,

4,4'-diphenyldimethylmethane diisocyanate, 4,4'-dibenzyl

diisocyanate, dialkyldiphenylmethane diisocyanate,

tetraalkyldiphenylmethane diisocyanate, 1,3-phenylene

diisocyanate, 1,4-phenylene diisocyanate, and tolylene diisocyanate. These may be used alone or in a combination of two or more types.

[00501

In addition, an adduct obtained by reacting a

diisocyanate compound with a tri- or more-functional polyol

compound is obtained by reacting the diisocyanate compound

described above with a tri- or more-functionalpolyol compound.

Examples of the tri- or more-functional polyol compound

include tri- or more-functional compounds among the compounds

exemplified as the polyol which is a raw material of the

reaction product (B-1), and each compound may be used alone

or in a combination of two or more types.

[0051]

Among the above, isocyanurate of aliphatic diisocyanate

compounds is preferable, and isocyanurate of hexamethylene

diisocyanate (HDI) is more preferable.

[0052]

The mixing ratio of the reaction product (B-1) to the

isocyanate compound (B-2) in the isocyanate component B is

preferably in the range of30/70 - 99/1for the reaction product

(B-1)/the isocyanate compound (B-2), and more preferably in

the range of 50/50 to 99/1.

[00531

The reaction product (B-1) may preferably be a reaction

product obtained by reacting the polyol, 4,4'-diphenylmethane diisocyanate, and the isocyanate compound (B-2) (hereinafter such a reaction product is referred to as the reaction product

"B-3") . By containing the reaction product (B-3), the

hardener is particularly excellent in long-term storability.

[0054]

Examples ofmore preferable combinations of the reaction

raw material of the reaction product (B-3) include

A reaction product (B-1-1) formed of a combination of

either or both of polyether polyol and polyester polyol as a

polyol (1), 4,4'-diphenylmethane diisocyanate, and an

isocyanurate of 1,6-hexamethylene diisocyanate as the

isocyanate compound (B-2)

A reaction product (B-1-2) formed of a combination of

either or both of polyether polyol or polyester polyol as a

polyol (1), 4,4'-diphenylmethane diisocyanate, and a biuret

of 1,6-hexamethylene diisocyanate as the isocyanate compound

(B-2)

A reaction product (B-1-3) formed of a combination of

either or both of polyether polyol or polyester polyol as a

polyol (1), 4,4'-diphenylmethane diisocyanate, and an

allophanate of 1,6-hexamethylene diisocyanate as the

isocyanate compound (B-2)

A reaction product (B-1-4) formed of a combination of

either or both of polyether polyol or polyester polyol as a

polyol (1), 4,4'-diphenylmethane diisocyanate, and an isocyanurate of isophorone diisocyanate as the isocyanate compound (B-2), and the like.

However, the present invention is not limited to these

combinations and it is possible to preferably use any reaction

product obtained by reacting the polyol, 4,4'-diphenylmethane

diisocyanate, and the isocyanate compound (B-2).

[00551

The number average molecular weight of the reaction

product (B-3) is preferably in the range of 500 to 3,000, and

more preferably in the range of 500 to 1,500 from the viewpoint

of an appropriate resin viscosity at the time of coating.

[00561

In addition, the reaction product (B-3) and the

isocyanate compound (B-2) may be used in a combination, which

is preferable. The combining method may be a method in which,

after the reaction product (B-3) is formed, it is also possible

to newly add the isocyanate compound (B-2), the amount of the

isocyanate compound (B-2) to be added as a raw material and

the reaction time in order to synthesize the reaction product

(B-3) are appropriately adjusted, and the reaction of the

reaction product (B-3) is finished in a state where a part of

the isocyanate compound (B-2) remains.

[0057]

(Other Isocyanate Compound (B-4))

The hardener of the present invention may include a general-purpose isocyanate compound (B-4) other than the reaction product (B-1) of the polyol and an isocyanate compound including at least 4,4'-diphenylmethane diisocyanate, and the isocyanate compound (B-2). In particular, in a case where an effect as a reactive diluent is expected, it is possible to use monoisocyanate compounds or diisocyanate compounds. From the viewpoint of suppressing the elution of non-intentional substances to a minimum, a diisocyanate compound is preferable, and it is possible to appropriately use the diisocyanate compound described above. Among the above, carbodiimide-modified diisocyanate and polymethylene polyphenyl polyisocyanate (also referred to as polymeric MDI or crude MDI) are preferable.

[00581

In a case where the general-purpose isocyanate compound

(B-4) is contained, the blending ratio of the isocyanate

compound (B-4) in the isocyanate component B is preferably in

the range of 50/50 to 99/1 for the reaction product

(B-1)/isocyanate compound (B-4), and more preferably in the

range of 70/30 to 97/3.

In addition, the isocyanate compound (B-2)/isocyanate

compound (B-4) is preferably in the range of 100/0 to 5/95,

and more preferably in the range of 100/0 to 20/80.

[00591

The number average molecular weight of each isocyanate compound used for the isocyanate component B is not particularly limited, but is usually adjusted in the range of

500 to 3000 fromthe viewpoint ofan appropriate resinviscosity

at the time of coating.

[00601

The blending ratio of the polyol component A containing

the polyol compound and the isocyanate component B containing

the isocyanate compound is an equivalent ratio [(a)/(b)] of

the solid content hydroxyl equivalent (a) of the polyol

compound and the solid content isocyanate equivalent (b) of

the polyisocyanate compound and is 1.0 to 5.0, and more

preferably 2.0 to 3.0. The details of the manufacturing are

described in the Examples. In addition, the concentration of

isocyanate group in the isocyanate component B is preferably

in the range of 5 to 20%.

[0061]

(Viscosity)

The two-component adhesive of the present invention

preferably blends the polyol component A and the isocyanate

component B in a weight ratio to have a viscosity of 5,000 mPa -s

or less after standing for 30 minutes in an atmosphere of 40°C.

In the present invention, the viscosity is a value measured

by a rotational viscometer under the following conditions.

Measuring apparatus; MCR-302 manufactured by Anton Paar GmhH

Measurement conditions: Temperature 40°C, cone plate # 50 mm

[00621

In addition, from the viewpoint of workability such as

mixing, the viscosity mPa -s at 40°C, 10 minutes after blending,

is preferably 3000 mPa-s or less, so that it is possible to

reduce variation in the coating amount. Although the lower

limit of the viscosity is not particularly limited, the lower

limit is often 500 mPa-s or more in consideration of the

viscosity of the raw material itself.

[0063]

As described above in detail, the two-component adhesive

of the present invention has the polyol component (A) and the

isocyanate component (B) as essential components; however,

further mixing an aliphatic cyclic amide compound with either

component out of the polyol component (A) and the isocyanate

component (B) or blending the aliphatic cyclic amide compound

as a third component during coating makes it possible to

effectively suppress the elution of harmful low molecular

chemical substances typified by aromatic amines in the

laminate package into the contents thereof.

[0064]

Examples ofthe aliphaticcyclicamide compoundusedhere

include 6-valerolactam, e-caprolactam, o-enanthollactam,

i-capryllactam, $-propiolactam, and the like. Among these,

e-caprolactam is preferable in terms of the excellent effect

of reducing the elution amount of low molecular chemical substances. In addition, regarding the blending amount, it is preferable to mix the aliphatic cyclic amide compound in a range of 0.1 to 5 parts by mass per 100 parts by mass of the polyol component A.

[00651

The two-component adhesive of the present invention may

be used in combination with a pigment, as necessary. The

usable pigments in this case are not particularly limited, and

examples thereof include organic pigments and inorganic

pigments described in "Paint Materials Handbook" 1970 edition

(edited by the Japan Paint Manufacturers Association) such as

extender pigments, white pigments, black pigments, gray

pigments, red pigments, brown pigments, green pigments, blue

pigments, metal powder pigments, luminescent pigments, and

pearlescent pigments, as well as plasticpigments and the like.

There are various specific examples of these coloring agents

and examples of organic pigments include various insoluble azo

pigments such as Benzidine Yellow, Hansa Yellow, and Laked 4R;

soluble azo pigments such as Laked C, Carmine 6B, and Bordeaux

10; various (copper) phthalocyanine pigments such as

phthalocyanine blue and phthalocyanine green; various

chlorine-based dyeing lakes such as Rhodamine lake and methyl

violet lake, various mordant dye pigments such as quinoline

lake and fast sky blue; various vat dye-based pigments such

as anthraquinone-based pigments, thioindigo-based pigment, and perinone-based pigments; various quinacridone pigments such as Syncasia Red B; various dioxazine pigments such as dioxazine violet; various condensed azo pigments such as chromophthal; aniline black and the like.

[00661

Examples of inorganic pigments include various

chromates such as chrome yellow, zinc chromate, and molybdate

orange; various ferrocyanic compounds such as Prussian blue;

various metaloxides suchas titaniumoxide, zincwhite, Mapico

yellow, iron oxide, bengala, chrome oxide green, and zirconium

oxide; various sulfides or selenides such as cadmium yellow,

cadmium red, and mercury sulfide; various sulfates such as

barium sulfate and lead sulfate; various silicates such as

calcium silicate and ultramarine blue; various carbonates such

as calcium carbonate and magnesium carbonate; various

phosphates such as cobalt violet and manganese violet; various

metal powders such as aluminum powder, gold powder, silver

powder, copper powder, bronze powder, and brass powder; flake

pigments and mica flake pigments of these metals; metallic

pigments and pearl pigments such as mica flake pigments and

mica iron oxide pigment in the form coated with metal oxide;

graphite, carbon black, and the like.

[0067]

Examples of extender pigments include precipitated

barium sulfate, Gohun pigment, precipitated calcium carbonate, calcium bicarbonate, white limestone, alumina white, silica, hydrous fine silica (white carbon), ultrafine anhydrous silica

(Aerosil), silica sand, talc, precipitated magnesium

carbonate, bentonite, clay, kaolin, ocher, and the like.

[00681

Furthermore, examples of plastic pigments include

"Grandoll PP-1000" and "PP-2000S" manufactured by DIC

Corporation, and the like.

[00691

As the pigments used in the present invention, inorganic

oxides such as titanium oxide and zinc white as the white

pigment and carbon black as the black pigment are more

preferable since these are excellent in durability, weather

resistance, and design properties.

[0070]

The mass ratio of the pigment used in the present

invention is 1 to 400 parts by mass with respect to the total

of 100 parts by mass of the isocyanate component (B) and the

polyol component (A) and more preferably 10 to 300 parts by

mass since the adhesion property, the blocking resistance, and

the like are excellent.

[0071]

It is also possible to use an adhesion promoter in the

two-component adhesive of the present invention. Examples of

adhesion promoters include coupling agents such as silane coupling agents, titanate-based coupling agents, and aluminum-based coupling agents, and epoxy resins.

[0072]

Examples of silane coupling agents include aminosilanes

such as y-aminopropyltriethoxysilane,

y-aminopropyltrimethoxysilane, N

(aminoethyl)-y-aminopropyltrimethoxysilane, N

(aminoethyl)-y-aminopropyltrimethyldimethoxysilane, and

N-phenyl-y-aminopropyltrimethoxysilane; epoxy silanes such

as $-(3,4-epoxycyclohexyl) ethyltrimethoxysilane,

y-glycidoxypropyltrimethoxysilane, and

y-glycidoxypropyltriethoxysilane; vinyl silanes such as

vinyltris ($-methoxyethoxy) silane, vinyltriethoxysilane,

vinyltrimethoxysilane, and

y-methacryloxypropyltrimethoxysilane; hexamethyldisilazane,

7-mercapto propyl trimethoxysilane, and the like.

[0073]

Examples of titanate coupling agents include

tetraisopropoxy titanium, tetra-n-butoxy titanium, butyl

titanate dimer, tetrastearyl titanate, titanium

acetylacetonate, titanium lactate, tetraoctylene glycol

titanate, titanium lactate, tetrastearoxy titanium, and the

like.

[0074]

Examples of aluminum coupling agents include acetoalkoxyaluminum dilsopropylate and the like.

[0075]

Examples of epoxy resins include various epoxy resins

such as generally commercially available bisphenol type epoxy

resins, novolak type epoxy resins, bisphenol$3-methylglycidyl

ethers, novolak resin$-methylglycidylethers, cyclicoxilane

type epoxy resins, and resorcin type epoxy resins.

[0076]

The two-component adhesive of the present invention may

contain other additives other than the above, as necessary.

Examples of additives include leveling agents, inorganic fine

particles such as colloidal silica and alumina sol, polymethyl

methacrylate-based organic fine particles, defoaming agents,

antisagging agents, wetting and dispersing agents, viscosity

modifiers, ultraviolet absorbing agents, metal inactivating

agents, peroxide decomposing agents, flame retardants,

reinforcing agents, plasticizers, lubricants, rustinhibitors,

fluorescent whitening agents, inorganic heat ray absorbers,

flameproofing agents, antistatic agents, dehydrating agents,

and the like.

[0077]

Itis possible tomix these pigments, adhesionpromoters,

and additives with either one of the isocyanate component B

or the polyol component A, or to blend these pigments, adhesion

promoters, and additives as a third component for use at the time of coating. Among these, in terms of workability, it is preferable to prepare a premix in which a pigment, an adhesion promoter, and an additive are preliminarily blended in the polyol component A as the polyol composition for lamination adhesives of the present invention and use the premix as a two-component adhesive.

[0078]

(Laminated Film)

The laminated film of the present invention is formed

by laminating first and second plastic films with an adhesive

layer of the two-component adhesive between the first and

second plastic films. Specifically, the laminated film is

obtained by coating the two-component adhesive on a first

plastic film and then laminating a second plastic film on the

coated surface and curing the adhesive layer. Examples

thereof include a method in which the two-component adhesive

is coatedon a firstplasticfilmby arollcoater coatingmethod,

and then another substrate is adhered thereto without passing

through a drying step. The coating conditions are preferably

an adhesive blended liquid viscosity of approximately 300 to

3000 mPa -s at 400C in a state of heating to 30°C to 90°C in a

normal roll coater, but the adhesive of the present invention

has a viscosity after blending and standing for 30 minutes in

the atmosphere at 40°C of 5000 mPa-s or less, thus, it is

possible to carry out coating without problems. In addition, the coating amount is preferably 0.5 to 5 g/m 2 , and more preferably approximately 0.5 to 3 g/m 2

.

[0079]

In addition, a film where printing ink is gravure or

flexographic-printed on the first plastic film may be used,

and even in this case, it is possible to obtain a favorable

laminated appearance. As the printing inks described above,

it is possible to use solvent-based, water-based, or active

energy ray-curable inks.

[0080]

In the case of using two-component adhesive used in the

present invention, the adhesive is cured in 12 to 72 hours at

room temperature or under heating after lamination so as to

develop practical physical properties.

[0081]

Examples of the first plastic film used herein include

polyethylene terephthalate (PET) films, nylon films, oriented

polypropylene (OPP) films, a K-coated film such as

polyvinylidene chloride, base films such as various vapor

deposition films, aluminum foil, and the like, and examples

of the second plastic film include sealant films such as cast

polypropylene (CPP) films, vacuum metalized casted

polypropylene (VMCPP) films, linear low density polyethylene

(LLDPE), low density polyethylene (LDPE), high density

polyethylene (HDPE), aluminum deposition non-low density polyethylene (VMLDPE) film, and the like as other base materials.

[0082]

In the present invention, an excellent multilayer film

appearance is obtained even when subjected to high speed

lamination with a solvent-free laminating machine, and, for

example, it is possible to exhibit a favorable appearance even

with high-speed processing of 200 m/min or more in a case of

a film configuration of polyethylene terephthalate (PET)

film/vacuum metalized casted polypropylene (VMCPP) film, or

350 m/min or more in a case of an OPP/CPP film configuration.

[0083]

(Package)

The package of the presentinventionis formedby forming

the laminated film into a bag shape, and more specifically,

the shape of the package is formedby heat sealing the laminated

film. In addition, in consideration of the application as a

package, required performances (ease of tearing and cutting

by hand), rigidity and durability required of the package (for

example, impact resistance, pinhole resistance, and the like),

and the like, it is also possible to laminate other layers as

necessary. Usually, the package includes a substrate layer,

apaper layer, a second sealant layer, anon-woven fabriclayer,

and the like. It is possible to use a known method as a method

of laminating other layers. For example, an adhesive layer may be provided between the other layers and laminated by a dry lamination method, a thermal lamination method, a heat-sealing method, an extrusion lamination method, or the like. As the adhesive, the two-component adhesivemaybe used, or another one-liquid urethane adhesive, epoxy adhesive, aqueous dispersion of an acid-modified polyolefin, or the like may be used.

[0084]

Examples of specific laminate configurations include

first plastic film layer/adhesive layer/second plastic layer,

or base layer/adhesive layer/first plastic film

layer/adhesive layer/second plastic layer, in which the first

plastic layer is a barrier layer, which are able to be suitably

used for general packaging, lids, refill containers, and the

like; second plastic layer/paper layer, adhesive layer/first

plastic film layer/adhesive layer/second plastic, or second

plastic layer/paper layer/polyolefin resin layer/base

material layer/first plastic layer/adhesive layer/second

plastic layer/paper layer/first plastic film layer/adhesive

layer/sealant layer, which are able to be suitably used as a

paper container, a paper cup, and the like; second plastic

layer/adhesive layer/first plastic layer/adhesive

layer/second plastic layer or the like, which are able to be

suitably used for a tube container. These laminates may have

a print layer, a top coat layer, and the like as necessary.

[00851

As the first plastic film layer, for example, it is

possible to use a polyester resin film such as polyethylene

terephthalate (PET), polyethylene naphthalate (PEN), and

polylactic acid (PLA); a polyolefin resin film such as

polypropylene; a polystyrene resin film; a polyamide resin

film such as nylon 6, and poly-p-xylylene adipamide (MXD6

nylon); a polycarbonate resin film; a polyacrylonitrile resin

film; a polyimide resin film; and multi-layered bodies,

mixtures, or the like of the above (for example, Nylon

6/MXD6/Nylon 6, Nylon 6/ethylene-vinyl alcohol

copolymer/Nylon 6). Among the above, layers havingmechanical

strength and dimensional stability are preferable. In

particular, among the above, a film arbitrarily stretched in

a biaxial direction is preferably used.

[00861

In addition, as the first plastic film layer, it is

possible to adopt a deposited layer using aluminum vapor

deposition, silica vapor deposition, alumina vapor deposition,

silica alumina binary vapor deposition or the like in addition

to a soft metal foil such as aluminum foil in order to provide

a barrier function; and an organic barrier layer or the like

formed of vinylidene chloride resin, modified polyvinyl

alcohol, ethylene vinyl alcohol copolymer, MXD nylon, or the

like.

[00871

As the second plastic film layer, it is possible to use

a sealant resin known in the related art. Examples thereof

include polyethylene such as low density polyethylene (LDPE),

linear low density polyethylene (LLDPE), or high density

polyethylene (HDPE), polyolefin resins such as acid-modified

polyethylene, polypropylene (PP), acid-modified

polypropylene, copolymerized polypropylene, ethylene-vinyl

acetate copolymers, ethylene-(meth)acrylic acid ester

copolymers, ethylene-(meth)acrylic acid copolymers, and

ionomers. Among the above, from the viewpoint of

low-temperature sealability, polyethylene resins are

preferable and polyethylene is particularly preferable in

terms of low cost. The thickness of the sealant layer is not

particularly limited, but, in consideration ofprocessability

into a packaging material, heat sealability, and the like, is

preferably in the range of 10 to 60 pm, and more preferably

in the range of 15 to 40 pm. In addition, it is possible to

impart slipperiness to the sealant layer and packaging

material tearability by providing the sealant layer with

unevenness having a height difference of 5 to 20 pm.

[00881

Examples of the paper layer include natural paper,

syntheticpaper, and the like. Itispossible to form the first

and second sealant layers of the same material as the sealant layer described above. As necessary, a print layer may be provided on the outer surface or the inner surface side of the base material layer and the paper layer.

[00891

The "other layers" may include known additives and

stabilizers, for example, an antistatic agent, an easily

adhered coating agent, a plasticizer, a lubricant, an

antioxidant, and the like. In addition, the surface of the

film of the "other layer" may be subjected to a corona treatment,

a plasma treatment, an ozone treatment, a chemical treatment,

a solvent treatment, or the like as a pretreatment in order

to improve the adhesion in a case of laminating with other

materials.

[00901

As various forms of the package of the present invention,

there are a three-sided sealed bag, a four-sided sealed bag,

a gusset packaging bag, a pillow packaging bag, a Gebel top

type bottomed container, a Tetra-Classic, a brick pack, a tube

container, a paper cup, a lid material, or the like. In

addition, the package of the presentinventionmaybe subjected

to an easy opening treatment and provided with a resealable

means as appropriate.

[0091]

It is possible to industrially use the package of the

present invention as a package primarily for filling with foods, detergents, or medicines. For specific uses of the package, detergents andmedicines include liquid detergents for laundry, liquid detergents for kitchens, liquid detergents for baths, liquid soaps for baths, liquid shampoos, liquid conditioners, and pharmaceutical tablets. In addition, it is also possible to use the package in a secondary package which packages the container described above. In particular, since the two-component adhesive is used, it is possible to suitably use the package as a package for food and pharmaceutical applications in which elution is a problem.

Examples

[0092]

Next, a specific description willbe given of the present

invention using Examples and Comparative Examples. Unless

otherwise stated, "parts" and "%" are on a mass basis.

[0093]

Synthesis Example 1 [Synthesis of Polyol Component Al]

560 parts by mass of diethylene glycol were added into

a reaction vessel and heated to 80°C while stirring under a

nitrogen gas flow. Furthermore, while stirring, 600 parts by

mass of adipic acid were added into the reaction vessel and

heated to 150°C to 240°C to carry out an esterification reaction.

When the acid value reached 5 mg KOH/g or less, the reaction

vessel was gradually depressurized and reacted at 1 mmHg or

less and 200 to 240°C for one hour, and a polyester polyol resin

(abbreviated below as "polyol component Al") having hydroxyl

groups at both terminals and with an acid value of 0.8 mg KOH/g

and a molecular weight of approximately 840 was obtained.

[0094]

Synthesis Example 2 [Synthesis of Polyol Component A2]

690 parts by mass of diethylene glycol and 8 parts by

mass of trimethylolpropane were added into a reaction vessel,

and dissolved by heating at 80°C while stirringunder a nitrogen

gas flow. Furthermore, while stirring, 810 parts by mass of

adipic acid were added into the reaction vessel and heated to

150°C to 240°C to carry out an esterification reaction. When

the acid value reached 5 mg KOH/g or less, the reaction vessel

was gradually depressurized and reacted at 1 mmHg or less and

200 to 2200C for one hour, and a polyester polyol resin

(abbreviated below as "polyol component A2") having hydroxyl

groups at both terminals and with an acid value of 0.8 mg KOH/g

and a molecular weight of approximately 1270 was obtained.

[0095]

Synthesis Example 3 [Synthesis of Polyol Component A3]

333 parts by mass of 2-methyl-propanediol, 179 parts by

mass of ethylene glycol, and 39 parts by mass of

trimethylolpropane were added into a reaction vessel and

dissolved by heating at 80°C while stirring under a nitrogen

gas flow. Furthermore, while stirring, 106 parts by mass of

isophthalicacidand 610parts bymass ofadipicacidwere added into the reaction vessel and heated to 150°C to 240°C to carry out an esterification reaction. When the acid value reached mg KOH/g or less, the reaction vessel was gradually depressurized and reacted at 1 mmHg or less and 200 to 2400C for one hour, and a polyester polyol resin (abbreviated below as "polyol component A3") having hydroxyl groups at both terminals and with an acid value of 0.5 mg KOH/g and a molecular weight of approximately 2100 was obtained.

[00961

Synthesis Example 4 [Synthesis of Polyol Component A4]

319 parts by mass of diethylene glycol, 121parts by mass

of 2-methyl-propanediol, and 55 parts by mass of

trimethylolpropane were added into a reaction vessel and

dissolved by heating at 80°C while stirring under a nitrogen

gas flow. Furthermore, while stirring, 504 parts by mass of

adipic acid were added into the reaction vessel and heated to

150°C to 240°C to carry out an esterification reaction. When

the acid value reached 5 mg KOH/g or less, the reaction vessel

was gradually depressurized and reacted at 1 mmHg or less and

200 to 2200C for one hour, and a polyester polyol resin

(abbreviated below as "polyol component A4") having hydroxyl

groups at both terminals and with an acid value of 0.8 mg KOH/g

and a molecular weight of approximately 660 was obtained.

[0097]

Synthesis Example 5 [Synthesis of Polyol Component A5]

300 parts of polypropylene glycol (molecular weight:

approximately 3000, triol) and 700 parts of castor oil (trade

name: Kakukouich, refined castor oil manufactured by Itoh Oil

Chemicals Co., Ltd.) were added into a reaction vessel and

uniformly dissolved by heating at 60°C while stirring under

a nitrogen gas flow. A polyether castor oil polyol resin

having a hydroxyl value of 130 mg KOH/g (abbreviated below as

"polyol component A5") was obtained.

[00981

Synthesis Example 6 [Synthesis of Polyol Component A6]

122 parts by weight of ethylene glycol, 267 parts by mass

of neopentyl glycol, and 6 parts by weight of

trimethylolpropane were added into a reaction vessel and

heated to 80°C while stirring under a nitrogen gas flow.

Furthermore, while stirring, 516 parts by mass of adipic acid

and 90 parts by weight of isophthalic acid were added into the

reaction vessel and heated to 150°C to 240°C to carry out an

esterification reaction. When the acid value reached 5 mg

KOH/g or less, the reaction vessel was gradually depressurized

and reacted at 1 mmHg or less and 200 to 240°C for one hour,

and a polyester polyol resin (abbreviated below as "polyol

component A6") having hydroxyl groups at both terminals and

with an acid value of 0.8 mg KOH/g and a molecular weight of

approximately 1650 was obtained.

[00991

Example 1 [Synthesis of Isocyanate Component B1 as Hardener]

50 parts of an isocyanurate of 1,6-hexamethylene

diisocyanate (trade name, Desmodur N3300, manufactured by

Covestro AG), 489 parts of 4,4'-diphenylmethane diisocyanate

(trade name, Millionate MT-F, manufactured by Tosoh

Corporation), 422 parts of polypropylene glycol (molecular

weight: approximately 1000), and 39 parts of polypropylene

glycol (molecular weight: approximately 400) were added into

a reaction vessel, a reaction was carried out by heating at

80°C while stirring under a nitrogen gas flow, the reaction

vessel was cooled when the reaction was completed, and an

isocyanate component B1 having an isocyanate group

concentration of approximately 13.1% was obtained.

[0100]

Example 2 [Synthesis of Isocyanate Component B2 as Hardener]

10 parts of an isocyanurate of 1,6-hexamethylene

diisocyanate (trade name, Desmodur N3300, manufactured by

Covestro AG), 400 parts of 4,4'-diphenylmethane diisocyanate

(trade name Millionate MT-F, manufactured by Tosoh

Corporation), 536 parts of polypropylene glycol (molecular

weight: approximately 2000), and 54 parts of polypropylene

glycol (molecular weight: approximately 400) were added into

a reaction vessel, a reaction was carried out by heating at

80°C while stirring under a nitrogen gas flow, the reaction

vessel was cooled when the reaction was completed, and an isocyanate component B2 having an isocyanate group concentration of approximately 10.1% was obtained.

[0101]

Example 3 [Synthesis of Isocyanate Component B3 as Hardener]

50 parts of a biuret of 1,6-hexamethylene diisocyanate

(trade name, Desmodur N3200, manufactured by Covestro), 489

parts of 4,4'-diphenylmethane diisocyanate (trade name,

Millionate MT-F, manufactured by Tosoh Corporation), 422 parts

of polypropylene glycol (molecular weight: approximately

1000), and 39 parts of polypropylene glycol (molecular weight

approximately 400) were added into a reaction vessel, a

reactionwas carried outbyheatingat 80°Cwhile stirringunder

a nitrogen gas flow, the reaction vessel was cooled when the

reaction was completed, and an isocyanate component B3 having

an isocyanate group concentration of approximately 13.1% was

obtained.

[0102]

Example 4 [Synthesis of Isocyanate Component B4 as Hardener]

50 parts of an allophanate of 1,6-hexamethylene

diisocyanate (trade name, Basonat HA3000, manufactured by

BASF), 489 parts of 4,4'-diphenylmethane diisocyanate (trade

name, Millionate MT-F, manufactured by Tosoh Corporation), 422

parts of polypropylene glycol (molecular weight:

approximately 1000), and 39 parts of polypropylene glycol

(molecular weight: approximately 400) were added into a reaction vessel, a reaction was carried out by heating at 80C while stirring under a nitrogen gas flow, the reaction vessel was cooled when the reaction was completed, and an isocyanate component B4 having an isocyanate group concentration of approximately 13.0% was obtained.

[0103]

Example 5 [Synthesis of Isocyanate Component B5 as Hardener]

489 parts of 4,4'-diphenylmethane diisocyanate (trade

name, Millionate MT-F, manufactured by Tosoh Corporation), 422

parts of polypropylene glycol (molecular weight:

approximately 1000), and 39 parts of polypropylene glycol

(molecular weight: approximately 400) were added into a

reaction vessel, a reaction was carried out by heating at 80°C

while stirring under a nitrogen gas flow, the reaction vessel

was cooled when the reaction was completed, and a reaction

product (B-1-1) of a polyol and an isocyanate having an

isocyanate group at both terminals was obtained.

Subsequently, 50 parts of an isocyanurate of

1,6-hexamethylene diisocyanate (trade name, Desmodur N3300,

manufactured by Covestro AG) were added into the container and

stirred until uniform, and an isocyanate component B5 having

an isocyanate group concentration of approximately 13.1% was

obtained.

[0104]

Example 6 [Synthesis of Isocyanate Component B6 as Hardener]

50 parts of an isocyanurate of 1,6-hexamethylene

diisocyanate (trade name, Desmodur N3300, manufactured by

Covestro AG), 389 parts of 4,4'-diphenylmethane diisocyanate

(trade name, Millionate MT-F, manufactured by Tosoh

Corporation), 422 parts of polypropylene glycol (molecular

weight: approximately 1000), and 39 parts of polypropylene

glycol (molecular weight: approximately 400) were added into

a reaction vessel, a reaction was carried out by heating at

80C while stirring under a nitrogen gas flow, and the reaction

vessel was cooled to 600C when the reaction was completed.

Subsequently, 100 parts of carbodiimide-modified

diphenylmethane diisocyanate (trade name, Lupranate MM103

manufactured by BIP) were added into the container and stirred

until uniform, and an isocyanate component B6 having an

isocyanate group concentration of approximately 12.7% was

obtained.

[0105]

Example 7 [Synthesis of Isocyanate Component B7 as Hardener]

95 parts of an isocyanurate of 1,6-hexamethylene

diisocyanate (trade name, Desmodur N3300, manufactured by

Covestro AG), 371 parts of 4,4'-diphenylmethane diisocyanate

(trade name, Millionate MT-F, manufactured by Tosoh

Corporation), 402 parts of polypropylene glycol (molecular

weight: approximately 1000), and 37 parts of polypropylene

glycol (molecular weight: approximately 400) were added into a reaction vessel, a reaction was carried out by heating at

80C while stirring under a nitrogen gas flow, and the reaction

vessel was cooled to 600C when the reaction was completed.

Subsequently, 95 parts of carbodiimide-modified

diphenylmethane diisocyanate (trade name, Lupranate MM103

manufactured by BIP) were added into the container and stirred

until uniform, and an isocyanate component B7 having an

isocyanate group concentration of approximately 13.1% was

obtained.

[0106]

Example 8 [Synthesis of Isocyanate Component B8 as Hardener]

50 parts of an isocyanurate of 1,6-hexamethylene

diisocyanate (trade name, Desmodur N3300, manufactured by

Covestro AG), 389 parts of 4,4'-diphenylmethane diisocyanate

(trade name, Millionate MT-F, manufactured by Tosoh

Corporation), 422 parts of polypropylene glycol (molecular

weight: approximately 1000), and 39 parts of polypropylene

glycol (molecular weight: approximately 400) were added into

a reaction vessel, a reaction was carried out by heating at

80°C while stirring under a nitrogen gas flow, and the reaction

vessel was cooled to 60°C when the reaction was completed.

Subsequently, 50 parts of polymer diphenylmethane

diisocyanate (trade name, Lupranate M20S manufactured by BIP)

were added into the container and stirred until uniform, and

an isocyanate component B8 having an isocyanate group concentration of approximately 11.9% was obtained.

[0107]

Example 9 [Synthesis of Isocyanate Component B9 as Hardener]

95 parts of an isocyanurate of 1,6-hexamethylene

diisocyanate (trade name, Desmodur N3300, manufactured by

Covestro AG), 371 parts of 4,4'-diphenylmethane diisocyanate

(trade name, Millionate MT-F, manufactured by Tosoh

Corporation), 402 parts of polypropylene glycol (molecular

weight: approximately 1000), and 37 parts of polypropylene

glycol (molecular weight: approximately 400) were added into

a reaction vessel, a reaction was carried out by heating at

80°C while stirring under a nitrogen gas flow, and the reaction

vessel was cooled to 60°C when the reaction was completed.

Subsequently, 50 parts of polymer diphenylmethane

diisocyanate (trade name, Lupranate M20S manufactured by BIP)

were added into the container and stirred until uniform, and

an isocyanate component B9 having an isocyanate group

concentration of approximately 12.5% was obtained.

[0108]

Example 10 [Synthesis of Isocyanate Component B10 as Hardener]

30 parts of an isocyanurate of 1,6-hexamethylene

diisocyanate (trade name, Desmodur N3300, manufactured by

Covestro AG), 382 parts of 4,4'-diphenylmethane diisocyanate

(trade name, Millionate MT-F, manufactured by Tosoh

Corporation), 376 parts of polypropylene glycol (molecular weight: approximately2000), and161parts ofcastor oil (trade name: Kakukouich, refined castor oil manufactured by Itoh Oil

Chemicals Co., Ltd.) were added into a reaction vessel, a

reactionwas carried outbyheatingat 80Cwhile stirringunder

a nitrogen gas flow, and the reaction vessel was cooled to 60C

when the reaction was completed. Subsequently, 50 parts of

polymer diphenylmethane diisocyanate (trade name, Lupranate

M20S manufactured by BIP) were added into the container and

stirred until uniform, and an isocyanate component B10 having

an isocyanate group concentration of approximately 11.4% was

obtained.

[0109]

Example 11 [Synthesis of Isocyanate Component Bl as Hardener]

95 parts of an isocyanurate of 1,6-hexamethylene

diisocyanate (trade name, Desmodur N3300, manufactured by

Covestro AG), 371 parts of 4,4'-diphenylmethane diisocyanate

(trade name, Millionate MT-F, manufactured by Tosoh

Corporation), 402 parts of polypropylene glycol (molecular

weight: approximately 1000), and 37 parts of polypropylene

glycol (molecular weight: approximately 400) were added into

a reaction vessel, a reaction was carried out by heating at

80°C while stirring under a nitrogen gas flow, and the reaction

vessel was cooled to 60°C when the reaction was completed.

Subsequently, 48 parts of carbodiimide-modified

diphenylmethane diisocyanate (trade name, Lupranate MM103 manufactured by BIP) and 48 parts of polymer diphenylmethane diisocyanate (trade name, Lupranate M20S manufactured by BIP) were added into the container and stirred until uniform, and an isocyanate component Bl having an isocyanate group concentration of approximately 13.3% was obtained.

[0110]

Example 12 [Synthesis of Isocyanate Component B12 as Hardener]

87 parts of 1,6-hexamethylene diisocyanate isocyanurate

(trade name, Desmodur N3300, manufactured by Covestro AG), 390

parts of 4,4'-diphenylmethane diisocyanate (trade name,

Millionate MT-F, manufactured by Tosoh Corporation), 270 parts

ofpolyol component A6 (molecular weight: approximately 1600),

and 122 parts of polypropylene glycol (molecular weight:

approximately 2000) were added into a reaction vessel, a

reactionwas carried outbyheatingat 80°Cwhile stirringunder

a nitrogen gas flow, and the reaction vessel was cooled to 60°C

when the reaction was completed. Subsequently, 130 parts of

carbodiimide-modified diphenylmethane diisocyanate (trade

name, Lupranate MM103, manufactured by BIP.) were added into

the container and stirred until uniform, and an isocyanate

component B12 having an isocyanate group concentration of

approximately 16.8% was obtained.

[0111]

Example 13 [Synthesis of Isocyanate Component B13 as Hardener]

87 parts of a biuret of 1,6-hexamethylene diisocyanate

(trade name, Desmodur N3200, manufactured by Covestro), 390

parts of 4,4'-diphenylmethane diisocyanate (trade name,

Millionate MT-F, manufactured by Tosoh Corporation), 270 parts

ofpolyol component A6 (molecular weight: approximately 1600),

and 122 parts of polypropylene glycol (molecular weight:

approximately 2000) were added into a reaction vessel, a

reactionwas carried outbyheatingat 80Cwhile stirringunder

a nitrogen gas flow, and the reaction vessel was cooled to 60C

when the reaction was completed. Subsequently, 130 parts of

carbodiimide-modified diphenylmethane diisocyanate (trade

name, Lupranate MM103 manufactured by BIP) were added into the

container and stirred until uniform, and an isocyanate

component B13 having an isocyanate group concentration of

approximately 16.9% was obtained.

[0112]

Example 14 [Synthesis of Isocyanate Component B14 as Hardener]

87 parts of an allophanate of 1,6-hexamethylene

diisocyanate (trade name, Basonat HA3000, manufactured by

BASF), 390 parts of 4,4'-diphenylmethane diisocyanate (trade

name, Millionate MT-F, manufactured by Tosoh Corporation), 270

parts of polyol component A6 (molecular weight: approximately

1600), and 122 parts of polypropylene glycol (molecular

weight: approximately 2000) were added into a reaction vessel,

a reaction was carried out by heating at 80°C while stirring

under a nitrogen gas flow, and the reaction vessel was cooled to 600C when the reaction was completed. Subsequently, 130 parts of carbodiimide-modified diphenylmethane diisocyanate

(trade name, Lupranate MM103 manufactured by BIP) were added

into the container and stirreduntiluniform, and anisocyanate

component B14 having an isocyanate group concentration of

approximately 16.6% was obtained.

[0113]

Comparative Example 1 [Synthesis of Isocyanate Component Cl

as Hardener]

539 parts of 4,4'-diphenylmethane diisocyanate (trade

name, Millionate MT-F, manufactured by Tosoh Corporation), 422

parts of polypropylene glycol (molecular weight:

approximately 1000), and 39 parts of polypropylene glycol

(molecular weight: approximately 400) were added into a

reaction vessel, a reaction was carried out by heating at 80°C

while stirring under a nitrogen gas flow, and the reaction

vessel was cooled when the reaction was completed, and an

isocyanate component Cl having an isocyanate group

concentration of approximately 13.6% was obtained.

[0114]

Comparative Example 2 [Synthesis of Isocyanate Component C2

as Hardener]

200 parts of a 50/50 mixture of 4,4'-diphenylmethane

diisocyanate and2,4-diphenylmethane diisocyanate (trade name,

Lupranate MI manufactured by BIP), 339 parts of

4,4'-diphenylmethane diisocyanate (trade name, Millionate

MT-F manufactured by Tosoh Corporation), 422 parts of

polypropylene glycol (molecular weight: approximately 1000),

and 39 parts of polypropylene glycol (molecular weight:

approximately 400) were added into a reaction vessel, a

reactionwas carried outbyheatingat 80Cwhile stirringunder

a nitrogen gas flow, and the reaction vessel was cooled when

the reaction was completed, and an isocyanate component C2

having an isocyanate group concentration of approximately

13.6% was obtained.

[0115]

(Hardener: Method for Evaluating Solution Stability)

Normal temperature: 100 g of a hardener was placed in

a sealed container and the solution stability was evaluated

after being left at normal temperature. The solution

stability evaluation during normal temperature storage was as

follows.

Solution stability evaluation 1: precipitated in 1 week or less

Solution stability evaluation 2: precipitated in 1 to 4 weeks

or less

Solution stability evaluation 3: precipitated in 4 to 12 weeks

or less

Solution stability evaluation 4: not precipitated after 12

weeks or more

Refrigeration: 100 g of a hardener was placed in a sealed container and the solution stability was evaluated after being left in a refrigerator (5°C) . The solution stability evaluation at the time of refrigerator storage was as follows.

Solution stability evaluation 1: precipitated in 1 week or less

Solution stability evaluation 2: precipitated in 1 to 3 weeks

or less

Solution stability evaluation 3: precipitated in 3 to 8 weeks

or less

Solution stability evaluation 4: not precipitated after 8

weeks or more

The results are shown in Table 1.

[01161

[Table 1]

Table 1 Hardener Solution stability evaluation Reaction product (B-1) Isocyanate (B-2) Reaction Reactive diluent (B-4) Normal Cooling product (B-3) tempera ture Example 1 1 PPG+4,4MDI HDI isocyanurate Present Absent 3 3 Example 2 B2 PPG+4,4MDI HDI isocyanurate Present Absent 3 3 Example 3 B3 PPG+4,4MDI HDI biuret Present Absent 3 2 Example 4 B4 PPG+4,4MDI HDI allophanate Present Absent 3 2 Example 5 B5 PPG+4,4MDI HDI isocyanurate Absent Absent 2 2 Example 6 B6 PPG+4,4MDI HDI isocyanurate Present Carbodiimide modified MDI 4 4 Example 7 B7 PPG+4,4MDI HDI isocyanurate Present Carbodiimide modified MDI 4 4 Example 8 B8 PPG+4,4MDI HDI isocyanurate Present Crude MDI 4 4 Example 9 B9 PPG+4,4MDI HDI isocyanurate Present Crude MDI 4 4 Example 10 B10 PPG+Castor oil+4,4MDI HDI isocyanurate Present Crude MDI 4 4 Example 11 B11 PPG+4,4MDI HDI isocyanurate Present Carbodiimide modified MDI 4 4 Crude MDI Example 12 B12 PPG+polyol component HDI isocyanurate Present Carbodiimide modified MDI 4 4 A6+4,4MDI Example 13 B13 PPG+polyol component HDI biuret Present Carbodiimide modified MDI 4 3 A6+4,4MDI Example 14 B14 PPG+polyol component HDI allophanate Present Carbodiimide modified MDI 4 3 A6+4,4MDI Comparative C1 PPG+4,4MDI Absent Absent Absent 1 1 Example 1 Comparative C2 PPG+liquid MDI Absent Absent Absent 4 4 Example 2

[0 117 ]

"Reaction product (B-3)" in Table 1 represents the

presence of the reaction product (B-3) obtained by reacting

the reaction product (B-1) with the isocyanate (B-2) and

"present" represents that the reaction product (B-1) and the

isocyanate (B-2) are reacted, and "absent" represents that the

reaction product (B-1) and the isocyanate (B-2) are not reacted.

In addition, "Reactive diluent (B-4) " represents an isocyanate

(B-2), that is, an isocyanate compound other than isocyanurates, biurets, allophanates, and adducts of diisocyanate.

In addition, HDIis an abbreviation of1,6-hexamethylene

diisocyanate, PPG is an abbreviation of polypropylene glycol,

4,4 MDI is an abbreviation of 4,4'-diphenylmethane

diisocyanate, and liquid MDI is an abbreviation of liquid

diphenylmethane diisocyanate.

[0118]

(Examples and Comparative Examples of Two-Component Adhesive)

Two-component adhesives were obtained according to the

combinations of Tables 2 and 3.

[0119]

(Evaluation Method)

[Evaluation of Harmful Component (PAA) Elution Amount]

The two-component adhesives blended according to the

combinations of the Examples or the Comparative Examples were

coated on a PET film such that the solid content coating amount

was approximately 3.0 g/m 2 , and the coated surface of this film

and the CPP film were bonded with a laminator and a lamination

film was manufactured. This laminated film was stored in a

40°C thermostat for 3 days.

This laminated film was cut to be 120 mm x 220 mm, folded

such that CPP was inside, and heat sealed in three directions

at 10 mm width, 1 atm, and 190°C for one second, to make a pouch

in which the contents contact 2 dm 2 . A 3% acetic acid vinegar solution was added to the contents. After retort sterilization of the packed pouch at 121°C for 0.5 hours, PAA was measured by LC/MS/MS.

[0120]

[Viscosity Measurement After 30 Minutes at 400CAfter Blending]

The viscosity was measured by a rotational viscometer

under the following conditions to obtain an mPa-s value.

Measuring apparatus; MCR-302 manufactured by Anton Paar GmbH

Measurement conditions: Temperature 400C, cone plate # 50 mm

The viscosity evaluation was as follows.

Viscosity evaluation 1: 1000 to 3000 mPa-s

Viscosity evaluation 2: 3000 to 4000 mPa-s

Viscosity evaluation 3: 4000 to 5000 mPa-s

Viscosity evaluation 4: 5000 mPa-s or more

[0121]

[Laminate Strength]

Two-component adhesives blended according to the

combinations of Examples or Comparative Examples were coated

on a PET film on which a pattern was gravure-printed with

printing ink Univia NT (manufactured by DIC) so as to have a

solid content coating amount of approximately 3.0 g/m 2 .

Thereafter, the coated surface of the film and the LLDPE film

were laminated with a laminator to produce a laminated film.

The laminated film was stored in a thermostat at 400C for 3

days to make a laminated film for a laminate strength test.

A test piece was cut out of the laminated film to a width

of15mm, and the adhesion strength (N/15 mm) was measuredusing

a tensile tester at a peeling speed of 300 mm/min with T-type

peeling.

[0122]

(Laminate Strength After Storage of Isocyanate Component B

Over Time)

After the isocyanate components B1 to B14 and Cl to C2

were produced and then allowed to stand at 600C for 10 days,

two-component adhesives were blended according to the

combinations in the table, and the laminate strength was

measured in the same manner.

[0123]

[Laminate Strength and Appearance After Retort]

Two-component adhesives blended in the combinations of

Examples or Comparative Examples were coated on a PET film on

which a pattern was gravure-printed with printing ink Univia

NT (manufactured by DIC) so as to have a solid content coating

2 amount of approximately 3.0 g/m . Thereafter, the coated

surface of the film and the LLDPE film were laminated with a

laminator to produce a laminated film. This laminated film

was stored in a 40°C thermostat for 3 days.

This laminated film was cut to be 150 mm x 300 mm, folded

such that the LLDPE was inside, and heat sealed at 1 atm, and

180°C for one second, to make a pouch. As the contents, 1/1/1 sauce (meat sauce: vegetable oil: vinegar = 1: 1: 1) was added thereto.

The filled pouch was subjected to steam sterilization

at 1210C for 30 minutes. The contents were removed, a test

piece was cut from the laminated film with a width of 15 mm,

and the adhesion strength (N/15 mm) was measuredusing a tensile

tester at a peeling speed of 300 mm/min with T-type peeling.

In addition, the appearance of each pouch after the

removal of the contents was observed, and the following

evaluation was performed according to the presence or absence

of the generation of delamination.

Evaluation 0: No delamination

Evaluation A: 5 or fewer points of delamination

Evaluation X: 6 or more points of delamination

[0124]

(Laminate strength and appearance after retort after storage

of isocyanate component B over time)

After the isocyanate components B1 to B14 and Cl to C2

were produced and then allowed to stand at 600C for 10 days,

two-component adhesives were blended according to the

combinations in the table, and the laminate strength and

appearance after retort were evaluated in the same manner.

[0125]

The results are shown in Tables 2 to 5.

[0126]

[Table 2]

Table 2 Example Example ExampleExample Example Example Example 15 16 17 18 19 20 21 Blend Polyol component A2 50 50 50 50 50 Polyol component A4 50 Polyol component A5 60 Isocyanate component B1 100 100 100 Isocyanate component B2 100 Isocyanate component B3 100 Isocyanate component B4 100 Isocyanate component B5 100 Isocyanate component B6 Isocyanate component B7 Isocyanate component B8 Isocyanate component B9 Isocyanate component B10 Isocyanate component B11 Isocyanate component B12 Isocyanate component B13 Isocyanate component B14 Evaluation PAA elution amount 10 ppb or 10 ppb or 10 ppb 10 ppb or 10 ppb or 10 ppb or 10 ppb or less less or less less less less less Lamination strength 5.1 4.7 4.8 4.4 4.2 4.2 4.3 Lamination strength after retort 5.2 5.1 5.1 4.7 4.5 4.1 3.8 Appearance after retort 0 0 0 0 0 0 0 Viscosity after 10 minutes at 1 1 1 1 1 1 1 40°C after blending mPa-s Viscosity after 20 minutes at 2 2 2 2 2 2 1 40°C after blending mPa-s Viscosity after 30 minutes at 3 3 3 3 3 3 2 40°C after blending mPa-s Evaluation of isocyanate component B after storage over time Lamination strength 4.8 4.6 4.7 4.2 4.3 4.1 3.9 Lamination strength after retort 5 4.9 5.0 4.6 4.3 4.0 3.8 Appearance after retort 0 0 0 0 0 0 0 Viscosity after 10 minutes at 1 1 1 1 1 1 1 40°C after blending mPa-s Viscosity after 20 minutes at 2 2 2 2 2 2 1 40°C after blending mPa-s Viscosity after 30 minutes at 3 3 3 3 3 3 2 40°C after blending mPa-s

[0127]

[Table 31

Table 3 Example Example Example Example Example Example Example 22 23 24 25 26 27 28 Blend Polyol component A2 Polyol component A4 40 50 50 50 50 50 Polyol component A5 60 Isocyanate component B1 Isocyanate component B2 100 Isocyanate component B3 100 Isocyanate component B4 100 Isocyanate component B5 100 Isocyanate component B6 100 Isocyanate component B7 100 Isocyanate component B8 100 Isocyanate component B9 Isocyanate component B10 Isocyanate component B11 Isocyanate component B12 Isocyanate component B13 Isocyanate component B14 Evaluation PAA elution amount 10 ppb or 10 ppb or 10 ppb or 10 ppb or 10 ppb or 10 ppb or 10 ppb or less less less less less less less Lamination strength 4.4 4.3 4.4 4.1 4.2 4.5 4.2 Lamination strength after retort 4.0 4.1 3.9 3.7 3.7 3.6 3.9 Appearance after retort 0 0 0 0 0 0 0 Viscosity after 10 minutes at 1 1 1 1 1 1 1 40°C after blending mPa-s Viscosity after 20 minutes at 2 2 2 2 2 2 1 40°C after blending mPa-s Viscosity after 30 minutes at 3 3 3 3 3 3 2 40°C after blending mPa-s Evaluation of isocyanate component B after storage over time Lamination strength 4.3 4.2 4.2 4.1 4.1 4.3 4.1 Lamination strength after retort 4.1 3.8 3.7 3.7 3.7 3.6 3.5 Appearance after retort 0 0 0 0 0 0 0 Viscosity after 10 minutes at 1 1 1 1 1 1 1 40°C after blending mPa-s Viscosity after 20 minutes at 2 2 2 2 2 2 1 40°C after blending mPa-s Viscosity after 30 minutes at 3 3 3 3 3 3 2 40°C after blending mPa-s

[01281

[Table 41

Table 4 Example Example Example Example Example Example 29 30 31 32 33 34 Blend Polyol component A2 Polyol component A4 45 50 60 60 60 Polyol component A5 50 Isocyanate component B1 Isocyanate component B2 Isocyanate component B3 Isocyanate component B4 Isocyanate component B5 Isocyanate component B6 Isocyanate component B7 Isocyanate component B8 Isocyanate component B9 100 Isocyanate component B10 100 Isocyanate component B11 100 Isocyanate component B12 100 Isocyanate component B13 100 Isocyanate component B14 100 Evaluation PAA elution amount 10 ppb or 10 ppb or 10 ppb or 10 ppb or 10 ppb or 10 ppb or less less less less less less Lamination strength 4.6 4.6 4.2 4.7 4.3 4.3 Lamination strength after retort 4.1 4.1 3.7 4.2 3.9 4.3 Appearance after retort 0 0 0 0 0 0 Viscosity after 10 minutes at 1 1 1 1 1 1 40°C after blending mPa-s Viscosity after 20 minutes at 2 1 2 2 2 2 40°C after blending mPa-s Viscosity after 30 minutes at 3 2 3 3 3 3 40°C after blending mPa-s Evaluation of isocyanate component B after storage over time Lamination strength 4.6 4.4 4.1 4.7 4.3 4.1 Lamination strength after retort 4.4 4.3 4.1 4.2 4.1 3.9 Appearance after retort 0 0 0 0 0 0 Viscosity after 10 minutes at 1 1 1 1 1 1 40°C after blending mPa-s Viscosity after 20 minutes at 2 1 2 2 2 2 40°C after blending mPa-s Viscosity after 30 minutes at 3 2 3 3 3 3 40°C after blending mPa-s

[0129]

[Table 51

Table 5 Comparative Comparative Comparative Comparative Comparative Comparative Example 3 Example 4 Example 5 Example 6 Example 7 Example 8 Blend Polyol component A2 50 50 Polyol component A4 50 50 Polyol component A5 50 50 Isocyanate component C1 100 100 100 Isocyanate component C2 100 100 100 Evaluation PAA elution amount 10 ppb or 100 ppb or 10 ppb or 100 ppb or 10 ppb or 100 ppb or less more less more less more Lamination strength 4.9 4.7 4.1 3.9 4.1 3.8 Lamination strength after retort 5.1 5 3.9 3.6 3.6 3.5 Appearance after retort 0 0 0 0 0 0 Viscosity after 10 minutes at 1 1 1 1 1 1 40°C after blending mPa-s Viscosity after 20 minutes at 2 2 2 1 2 1 40°C after blending mPa-s Viscosity after 30 minutes at 4 3 3 2 3 2 40°C after blending mPa-s I Evaluation of isocyanate component B after storage over time Lamination strength 4.9 4.8 3.9 3.9 3.7 3.5 Lamination strength after retort 5.1 5 3.5 3.6 3.5 3.3 Appearance after retort 0 0 0 0 0 0 Viscosity after 10 minutes at 1 1 1 1 1 1 40°C after blending mPa-s Viscosity after 20 minutes at 2 2 2 1 2 1 40°C after blending mPa-s Viscosity after 30 minutes at 4 3 3 2 3 2 40°C after blending mPa-s

[0130]

As a result, the two-component adhesives obtained in the

Examples had a viscosity of 5000 mPa -s or less after 30 minutes

at 40°C after blending and exhibited a long pot life, and the

PAA elution amount was 10 ppb or less. In addition, the

laminate strength and appearance were also excellent. On the

other hand, Comparative Examples 3 to 8 were all examples which

did not include the isocyanate compound (B-2). Although the

PAA elution amount in Comparative Example 3 was 10 ppb or less,

the viscosity after 30 minutes at 40°C after blending exceeded

6000 mPa-s from an early stage (after 20 minutes) after the

blending. In addition, in Comparative Examples 4, 6, and 8,

the viscosity after 30 minutes at 40°C after blending was 5000

mPa -s or less and there was no problem with the pot life, but

the PAA elution amount exhibited an extremely high value of

100 ppb or more. In Comparative Examples 5 and 7, the laminate

strength after retort decreased after storage over time of the

isocyanate component B.

Claims (10)

1. A hardener for a two-component adhesive, comprising: - a reaction product (B-1) of a polyol and an isocyanate compound including at least 4,4'-diphenylmethane diisocyanate; and - at least one isocyanate compound (B-2) selected from the group consisting of: a diisocyanate isocyanurate, a diisocyanate biuret, and a diisocyanate allophanate, wherein the reaction product (B-1) and the isocyanate compound (B-2) are reacted.

2. The hardener for a two-component adhesive according to claim 1, which includes a reaction product (B-3) of the reaction product (B-1) and the isocyanate compound (B-2), and the isocyanate compound (B-2).

3. The hardener for a two-component adhesive according to claim 1 or 2, wherein the reaction product (B-1) includes 4,4'-diphenylmethane diisocyanate, which is a raw material, at a content in a range of 90 to 99% by weight based on a total weight of all isocyanate compounds of the reaction product (B 1).

4. The hardener for a two-component adhesive according to any one of claims 1 to 3, which is of a solvent-free type.

5. A two-component adhesive comprising: - a polyol component A including a polyol compound; and - an isocyanate component B including an isocyanate compound, wherein the isocyanate component B includes a reaction product (B-1) of a polyol and an isocyanate compound including at least 4,4'-diphenylmethane diisocyanate, and at least one isocyanate compound (B-2) selected from the group consisting of a diisocyanate isocyanurate, a diisocyanate biuret, and a diisocyanate allophanate, and the reaction product (B-1) and the isocyanate compound(B-2) are reacted.

6. The two-component adhesive according to claim 5, wherein the reaction product (B-1) is a reaction product of a polyol,

4,4'-diphenylmethane diisocyanate, and the isocyanate compound (B-2).

7. The two-component adhesive according to claim 5 or 6, wherein the reaction product (B-1) includes 4,4' diphenylmethane diisocyanate, which is a raw material, at a content in a range of 90 to 99% by weight based on a total weight of all isocyanate compounds of the reaction product (B 1).

8. The two-component adhesive according to any one of claims 5 to 7, which is of a solvent-free type.

9. A laminated film comprising a laminate of a first plastic film, a second plastic film, and an adhesive layer between the first and second plastic films, wherein the adhesive layer is a layer of the two-component adhesive according to any one of claims 5 to 8.

10. A package comprising a bag-shaped, laminated film comprising a laminate of a first plastic film, a second plastic film, and an adhesive layer between the first and second plastic films, wherein the adhesive layer is a layer of the two-component adhesive according to any one of claims 5 to 8.